A hurdy-gurdy is a stringed musical instrument, with a rounded wooden body and a keybox. The hurdy-gurdy is played by turning a rosined wheel with a crank; the wheel rubs the strings and acts like a violin’s bow. It’s a period instrument – the Sforza Book of Hours, c.1490, shows an angel playing a hurdy-gurdy – but no examples have been found in period armory.
The hurdy-gurdy has no defined default orientation, so it must be blazoned explicitly (e.g., “crank to chief”, as in the illustration).
Goerijs Goriszoon bears: Per bend Or and sable, a sword bendwise and a hurdy-gurdy bendwise, crank to base, counterchanged.
Gardner of Elyg bears: Argent, a skeleton statant affronty sable playing a hurdy-gurdy azure.